Trump sends Boeing shares plunging after 'cancelling' Air Force One order

AEROSPACE giant Boeing saw its shares plunge in pre-market trading on Tuesday, after President-elect Donald Trump threatened to cancel an order for a new Air Force One airplane from the company amid a row over costs.

Boeing has made planes for US presidents since 1943, and the current Air Force One boasts 4,000 square feet of floor space that includes a conference/dining room, two galleys that can provide 100 meals at one sitting and areas for the presidential staff, media and crews.

In a statement Boeing today said: "We are currently under contract for $170 million to help determine the capabilities of these complex military aircraft that serve the unique requirements of the President of the United States.

"We look forward to working with the U.S. Air Force on subsequent phases of the program allowing us to deliver the best planes for the President at the best value for the American taxpayer."

Donald Trump's most memorable tweets as president

Donald Trump's most memorable tweets since elected as President of the United States

Mr Trump's twitter outburst comes after he proclaimed last week, also on social media, that he will leave his businesses in order to focus on running the US as president and to avoid conflicts of interest.

The president-elect has faced questions over the potential for a conflict of interest between his role in the White House and his business empire.

He said: "Legal documents are being crafted which take me completely out of business operations. The presidency is a far more important task!"